The etched porcelain laminate (a.k.a. porcelain veneer) and composite laminate have been demonstrated clinically for six years, but both present major limitations. These materials are excellent for masking unsightly teeth and are readily bonded to tooth structure with a variety of dental bonding agents. Their limitations, however, are based upon construction of these items at a minimum thickness of 0.4 to 0.5 mm. Thinner laminates do not have adequate shear and tensile strength and shatter easily. Because of this, natural teeth need to be reduced considerably in order to compensate for the thickness of the laminate. Non-reduction of tooth enamel in advance of bonding the laminate can result in tissue inflammation because of the increased bulk at the gingival margin and also can result in overbuilt, overcontoured, esthetically unpleasing laminates. A need exists, therefore, to fabricate ultra-thin laminates which will require no (or at least minimal) tooth reduction.
A need additionally exists to replace missing teeth with a minimum of tooth reduction of the adjacent abutment teeth. For many years a variety of precious and non-precious alloys have been used as internal structural components in conventional full-coverage porcelain bridgework, but both of these methods require extensive tooth reduction and metallic frameworks. The Manhattan Bridge (Golub) has been demonstrated in the Cloth Wrap Dental Process, U.S. Pat. No. 4,728,291, to include the application of fabric to the abutment teeth, bonding the fabric to the teeth, and sculpting the missing tooth in free-handed composite. This system has worked well, but because it is a free-handed system, it is difficult for many clinicians to finish and polish. The framework of the silk-resin Manhattan Bridge is ultimately surfaced in composite resin and, therefore, the technique must be considered provisional in light of the five and ten year wear tests of direct composite techniques.